Magneto timing indicator



March 21, 1933. J, F, MARTIN MAGNETO TIMING INDICATOR Filed Sept. 26, 1931 2 Sheets-Sheet l March 21, 1933. J. F. MARTIN 1,902,655

MAGNETO TIMING INDICATOR Filed Sept. 26, 1931 2 Sheets-Sheet 2 31% INVENTOR- 11221577 Martin.

BY m: A J

Patented Mar. 21, 1933 UNITED/ STATES PATENT OFFICE JOHN I. MARTIN, OF SPRINGFIELD, MASSACHUSETTS, ASSIGNOB '10 UNITED AMERICAN BOSCH GOBPQBLTIOH, OF SPRINGFIELD, MASSACHUSETTS, A UOBIORATION OF NEW YORK IAGNETO TIIDT G INDICATOR Application fled September 26, 1931. Serial No. 565,995.

The invention relates to improvements in magnetos, and especially to magnetos adapted to be connected to internal combustion engines and driven thereby'for the purpose of supplying electric energy to the igniters or spark plugs of the same.

An object of the invention is to provide a magneto having an indicator to enable the positions of the movable parts thereof, usually encased and hidden from view, to be readily ascertained.

Another object of the invention is to provide a simple and inexpensive indicator for quickly and easily timing a magneto by setting or adjusting its movable parts to operate in correct relation with the engine by which the magneto is actuated.

A further object of the invention is to provide a timing indicator of this character by utilizing one of the rotatable members of the magneto which is accessible and visible from the outside, so that the magneto can be set or timed when it is to be coupled to an engine, without need to remove, for example, the stationary distributor member or the cap or cover upon the housing for the interrupter mechanism.

Still another object of the invention is to supply a magneto having a sealed casing for the interrupter mechanism thereof and suitable means for mounting said casing on the housing or framework of the magneto.

Other objects as well as numerous advantages of the invention will appear in the following description taken with the drawings, in which a preferred embodiment of the invention is illustrated. The disclosure, however, is explanatory only; and alterations in structure may of course be made without departing from the principle of the invention or exceeding the scope and meanings of the terms of the appended claims.

On said drawings- Figure 1 is a side view partly in section of a magneto having a timing indicator according to my invention;

Figure :2 is an end view seen from the right of Figure l;

Figure 3 is a section on the line 33 of Figure 2;

Figures 4, 5 and 6 show in perspective the parts of the timing indicator; p

Figure 7 is a vertical, longitudinal section of one end of a magneto having an improved sealed casing for the interrupter mechanism;

Figure 8 is an end View seen from the right, of Figure 7 Figure 9 is a section on line 9-9 of Figure 7; 1

F izgure 10 is a section on line 10-h of Fi ure Figure 11 is a front view of the cam-ring in said casing; and

Figure 12 is a side view of said ring.

The same numerals identify the same parts throughout.

In practice the indicator comprises an element affixed to the projecting end or the distributor shaft; which, as illustrated in Figure 1, is visible within the bend of the permanent magnet or magnets of the magneto. This element rotates with the distributor shaft and the position thereof will at once reveal the relative positions of the rotor of the distributor, the armature and interrupter of the magneto. Hence one requires only to rotate the armature shaft until the indicator element reaches a predetermined point to be assured that the armature, the interrup'ter and the rotor of the distributor all occupy the desired positions to enable the magneto to be correctly geared to the engine with which it is to operate.

The magneto represented in the drawings is shown as of the high tension type; but the invention may be employed just as well with a low tension magneto, or magneto of quite different construction. The machine comprises a frame-work or housing 1, having an extension 2 on top; and this extension carries a bearing 3 for the main distributor shaft 4:. The extension 2 has a rim 5 to give it the shape of a gear casing; and adjacent this casing in the direction of the axis of the magneto, are disposed one or more permanent magnets 6. The poles of this magnet are' at each side of the armature chamher, and the end of the shaft 4c projects through the bearing 3 in extension 2 into the space below the top or bend of the magnet or magnets 6; and carries in. said space a pointer or element 7 which is fixed on the. projecting end of the shaft or member 4 and rotates therewith. Plainly, if this element is so disposed on the shaft that it is in substantial alignment with the rotating member of the distributor, the operator or attendant can always see at a glance, from the position of the element 7, what are the positions or the distributor arm and the interrupter without having to take off any of the covering Jarts of the magneto to look at these menu ers.

The armature is indicated at 8, and it is revolved by a shaft 9 which turns in a suitable hearing at one end 10 of the framework From the opposite end of the armature ejects a shaft or trunnion which will ree in a similar bearing in the extremity 11 the framework 1. This trunnion and the arings need not be shown as they are of tandard construction. The shaft or trunnion adjacent the extremity 11 will as usual project through to the outside of the magneto and carry most of the interrupter mechanism thereon. This interrupter will be within a casing shown in part at 12, mounted on the extremity 11, and closed at its outer end by a cap 13. An arm 14 on the casing permits adjustment to advance or retard the actuation of the interrupter.

The construction of the armature, the shafts and bearings for the same, and the interrupter mentioned above, are of course no part of my invention; but are necessarily related thereto and must be taken into account for an understanding of this improvement. The armature 8'carries just forward of the extension 2, a gear 15 which meshes with a gear 16 in the casing 5 afixed to the inner end of the shaft 4. This gear 16 car ries a suitably shaped piece of insulation 17, in the outer face of which is a radial strip 18 of metal electrically connected with a conducting brush 19 in a socket carried by the insulation 17. Between the gear 15 and the extremity 10 of the framework 1,- is the usual collector ring 20 of insulation bearing the metal slip ring 21 to which one i end of the high tension winding on the armature is united. in the casing 5 is another stationary member of insulation 22 with a socket carrying a conductive brush 23 that makes contact with the ring 21. The brush 23 is united by an embedded conductor 24 to a similar brush 25 in the insulation 22; this brush 25 being in line with the shafts and projecting from the insulation 22 to make contact with the metal inset 18. The insulation 22 bears a number of fixed contact pieces 26, at regular intervals apart and each of these contact pieces 26 will be engaged in turn by the brush 19 as the gear 16 revolves. The contact pieces 26 will be secured to metal sleeves 27 in the principal bosses 30 in which the ends of the high tension I leads to the spark plugs are inserted. Only one of these bosses is shown in Figure 1 but they will of course be equal in number to the number of engine cylinders.

-To mount my timing indicator on a magneto of this design, the distributor shaft 4 is caused to project from the outer end of the bearing 3 into the space beneath the top of the magnet as above stated; and for this purpose the extremity of the shaft is reduced as shown at 31 and "formed near its outer end with an encircling groove 32. The ele ment '2" has a hub 33 in the sides of which are slots which can be brought into registry with the groove 32 when the hub- 33 is mounted on the extremity 31. To hold the hub 33 on the extremity 31 1 provide a U- shaped clip 35, the arms of which will enter the two slots 34 and engage the groove 32. With the clip 35 in place, the hub 33 will still be free to turn slightly on the hub 31 but cannot be pulled 0d this extremity. It is of course also necessary that the hub 33 be made perfectly rigid with the extremity 31 so that it cannot rotate to vary the angular position of the element 7 with respect to the insulation 17; for this purpose 1 iorm the extremity 31 with an axial groove 36. 'Obviously when a part of the hub 33 is "forced into the groove 36, the rigid connection of the hub with the extremity 31 will be completed, and then the hub 33 and the member 7 are afi'ixed to the shaft 4. But before the hub 33 is made to engage the keyway 36, the shaft 9 is turned until the rotor arm 17 of the distributor is brought into engagement with say the first distributor terminal 26; that is, the terminal which will be connected to the ignit'er plug of the first cylinder of the en inc. The keyway 36 will be 180 removed irom the rotor arm 17 and when the latter engages the first distributor terminal 26, the element 7 can be turned on the extremity 31 until it is brought into alignment with the rotor arm 17.. Such position will be obtained by causing the element 7 to pointtowards a suitable mark M, in line with the first terminal 26 on the flange of a suitable cap-which is placed over one or more washers 37 at the outer end of the bearing 3 within the magnet or magnets 6. The cap in question is indicated at 38. Ttsout-turned rim is shown at 39 and it is centrally perforated to allow the extremity 31 to pass through it. The flange 39 may be perforated for screws 40 which enter openings in the end of the bearing 3 to hold the washers and cap in place. The mark M on the flange 39 gives the position for the element 7 when the rotor arm 17 engages the first terminal 26. By holding the element 7 against movement, while pointing towards the mark M, the mechanic can now by means of a. suitable tool, force a part of the hub 33 into the ke way 36 as indicated in Figure 3 at 33a. T e element 7 must then revolve with shaft 4 and whenever it points to the mark M, the corresponding position of the rotor arm 17 will be indicated.

The position of the interrupter mechanism must of course correspond to that of the rotor arm 17; that is, whenever the rotor arm reaches the first terminal 26 or any of the other terminals, the contact members of the interrupter will be so placed that the usual striking block on the lever of the interrupter is just about to engage with one of the operating cams on the inside of the casing 12. To connect the magneto with the en 'ne, the latter is now cranked so as to bring t e piston of the first cylinder up to the proper point at or near the end of the compression stroke thereof. Then the shaft 9 is connected to the shaft or other moving part of the engine which is geared to the crank shaft and the armature of the magento will then run in truly timed relation with the engine to cause igniters to spark in each cylinder in the order required for efficient operation.

Hence it is apparent that with an indicator of this character, the purpose of the invention can be fully served and the magneto can always he timed with reference to the engine from the outside of the magneto. Neither the distributor 28 nor the cap 13 of the interrupter need ever he removed. time the indicator element 7 is attached to the extremity 31 in approximate alignment with the arm 17, it will always mark the position when the rotor arm 17 makes contact with the first terminal 26: and even it the indicator is slipped oil the end of the shaft 4; correct remounting can always be obtained; because when the indicator is put back on the extremity 31 it will not go on the latter except when the indentation 336: re-enters the keyway 36.

The cap 38 may contain packing material 41 and the hearing 3, a lining 42. At 43 is a lubricating hrush or wick to conduct oil to the shaft 4.

ln Figures 7' to 12 inclusive the framework of the magneto-l is shown as having one end 11; intended to support the casing of the interrupter mechanism, shaped to provide an external cylindrical looss 44 upon which is placed a ring 45 which enters and bears a suitable carrier or sleeve 46. @ver this s eeve the interrupter casing 47 is slipped. lhis casing 47 may he made in any suitable mannor in one piece. It closed at one end and is large enough to receive and permit the operation of the interrupter mechanism in side of it. 'lhis interrupter mechanism is not shown, hut may he of any well known design.

The boss 44 may have its end bevelled and the ring 45 fits this boss snugly. Projecting from the outer circumference of the ring 45 is a screw 48 the head of which at its outer end lies in a recess 49 in the sleeve 46. The recess is as wide as needed for the purpose of timin the interrupter; that is, advancing or retar ing the instant of ignition.

The screw 48 fixes the range of timing ad justment and its inner end may bear on the bevelled face of the supporting part 44, so that the ring 45 cannot turn thereon. The sleeve 46 and casing 47. are connected together and the latter has an integral operating arm 50 by which the casing and sleeve can be shifted as far as the width of the recess 49 and the projection or head of the screw 48 permlt.

The casing 47 also bears an external conductor 51 which carries the terminal 52, or-

Between the end 11 or the housing of the ma neto and the rim of the casing 47 is a packing ring or gasket 53 of felt or the like received within the end of the framework 1 thus sealing the casing and making it proof against dust and moisture. The ring 45 may have an outturned rim or edge 54 at one end A to fit a circular slot 55 in the adjacent end of the framework 1 encircling the boss 44 and the sleeve 46 abuts this flange 55. Sur rounding this slot 55 is an annular shoulder 53% in the end 11' and the packing 53 seats against this shoulder and the outer edge of the rim 54. Hence the gasket is secured and displacement prevented.

The end ll of the framework 1 is of course centrally apertured, as shown at 57, to perunit one end oi the armature shalt, not shown, to project into the casing 47, and operate the interrupter mechanism as the armature revolves. T he end 11' also has an inside annular shoulder 58 for a hall bearing similar to the ball bearing in the end 10 on Figure l; and the ring 45 may have a central web 59 with an aperture 60 somewhat smaller than the aperture 57 but concentric with The casing 47 is held in place by a retaining clip 61 pivotally attached to a supporting post 62 at the hottom of the framework 1. The clip 61 is resilient and presses on the casing 47 at the middle but it can be swung to one side to clear the casing when this casing is to he dismounted.

Within the casing are projections 63 to enter recesses 64 in the sleeve 46, so that when the casing 47 is turned the sleeve 46 is moved with it. The sleeve 46 carries the usual cam projections held fast by the screws 66 to operate the movable lever of the interrupter mechanism. Hence when the arm 50 is actuated, both the casing 47 and sleeve 46 with the cam projections 65 are adjusted together.

The casin 47 .is of metal; and for properly connecting the outside terminal 51, the casing is pierced to carry a stud 67'which passes through the closed end of the casing and carries aifixed to its inner end a spring 68 having secured to its outer end a metal socket in which is a contact member 69. lhis contact will normally engage the fixed contact of the timer, which will be connected to one end of a generating winding on the armature in the usual way. The inner end of the stud 67 will he insulatedfrom the casing by a washer 70 and this stud will also be surrounded by insulating bushing 'Zl which has, at its end, outside of the casing 1, a squared head or saddle 72 with a recess in which the lower end of the terminal 51 is secured.- The sides of this saddle hold the terminal 51 so that it cannot move on the stud 67 as a pivot. Ribs or projections"? 3 on the exterior of the casing 4? at the sides of the saddle 72 prevent turning of the bushing Tl and thus the conductor 51 is made rigid with respectto the casing. I

This construction permits the casing 4? to be made in one piece and entirely separate from the interrupter mechanism including the cam projections in the sleeve 46. It

covers the timer or interrupter mechanism, efi ectiveiy protects it by shielding from dirt and moisture, and thus prevents interference with. the function of the interrupter and the proper operation oi? the magneto. lin this type of casing a short-circuit of the interrupter cannot take place. Likewise there is completely obviated the risk of breaking which often occurs when the casing is made in two pieces; one being in the form of a cyllnder open at looth ends and the other a cap of insulation which closes the outer end of such a cylinder. in my casing the cylindrical portion is integral with the closed end thereof, and maximum strength and durability are thus obtained The recess 49 is preferably in the bottom portion of the ring 46 so that it any moisture should collect in the casing, the clip 61 can be swung to one side to permit the casing 47 and ring 46 to be withdrawn enough to let the moisture drain out through the recess 49. The projection 63 and recess 64 can be located at any desired oints in the circumference of the casing 4 The cam blocks or projections 65 are provided with the usual recesses or apertures to receive oil wicks 74; a portion of these wicks extending through to the inside or operating face of these cam projections to lubricate the striker block on theinterrupter lever,

this flange; and as stated above the bevelled I face of the part 44-may be recessed to receive the inner end of the screw 48 to prevent the ring 45 from turning on the part 44. The

, tight fit between the flange 54 and groove 55 may he secured in any suitable manner. If desired, the ring 45 may be attached to the framework of the magneto when the housing is formed; as by casting the housing or framework oi the magneto upon this ring 45; that is causing the end 11', when the magneto framework is formed, to flow around the flange 55 and thus permanently afhxing the ring 45 to the end ll when the molten metal cools and solidifies. In that way there will he no need for the screw 48 to engage the part 44 because the ring 45 will then he held tightly enough in place.

Having thus described my invention, what ll believe to be new and desire to secure and protect by Letters Patent of the United States is I l. in a magneto having encased movable parts and means for continuously moving some, the combination of a continuously movable member having an enclosed portion and another portion projecting constantly into view and an element secured to said member to indicate the position of said parts.

2. in a magneto having encased movable parts and. means for continuously moving same, the combination of a continuously movahle member having an enclosed portion and another portion projecting constantly into view, the magneto bearing a visihle mark adjacent said last-named portion and ele ment on said last-named portion to (Bo-operate with said mark and indicate the position 5 of said parts.

3. ln s magneto having encased movable parts and means for continuously moving same, the combination of a rotatable shaft, the magneto having a framework providing a hearing for said shaft, the shaft having a reduced extremity projecting from said hearing constantly into view and a pointer on said extremity to indicate the positions of the movable parts within the magneto.

4. A magneto having encased movable parts comprising a rotatable shaft, the magneto including a housing and a hearing supported by said housing for said shaft, a perforated cap attached to the adjacent end of the hearing, said cap having a marked flange. the shaft projecting through the cap and an element on the shaft adjacent the exterior surface of the cap to co-operate with said marked flange and indicate constantly the positions of said movable parts on the inside hf said magneto.

5. A magneto having a framework enclosing interrupter and distributor a rotatable shaft forming part of said mechanism, a bearing supported by said frame- 5 work, and receiving said sha the latter having an extremity pro 'ec said hearing constantly into view, e extremi havmg an encircling groove and an ks way, a hub carrying a pointer on said 19 said hub having slots to register with sai groove, aretaining clip engaging the slots and groove, the hub having an indentation engaging the keyway so that the hub is held against turning or sliding on the shaft and 15 is compelled to rotate therewith, and a fixed mark on the bearing to co-operate with the inter. 6; 'The combination of a etc having a housin movable parts eniiosed by the housing, 0 said parts comprisin interrup-- ter an distributor mechanism, a aring on the housin the distributor mechanism comprising a aft in said bearing, the shaft having a reduced extremimrojectinrg from said 25 end of the bearing, a ged pe orated cap secured to the end of the bearing, said extremity extending from the cap, a mark on said cap and an indicator comprising a hub iwithapointeraflixedtosaidextremityto 36 show the positions of said parts.

7. In a magneto having encased movable parts and means for continuously moving same, the combination of a continuously movable member and an element secured to said 35 member and to view, from the outside of the magneto to indicate visually the position of sai parts.

8. In a magneto having encased movable parts and means for continuously moving same, the combination of acontinuously movable member and an element secured to said member and exposed to view fromthe outside of the ma etc to indicate visually the position of sai parts, the magneto bearing a visible mark to cooperate with said element.

In testimony whereof I aflix my signature.

JOHN 11 

